Grinder for involute bacon knife



April 11, 1961 R. A. RAINE GRINDER FOR INVOLUTE BACON KNIFE 3 Sheets-Sheet 1 Filed July 17, 1957 N 5 Q7 INVENTOR 2 41: CW

April 11, 1961 R. A. RAINE GRINDER FOR INVOLUTE BACON KNIFE 3 Sheets-Sheet 2 Filed July 17, 1957 .April 11, 1961 R. A. RAINE GRINDER FOR INVOLUTE BACON KNIFE 3 Sheets-Sheet 3 Filed July 1'7, 1957 INVENTOR. 7/4mQ Z gaze awn/r g hand. provide a,knife sharpening apparatus which is operable port. i r i Fig. 3 is a fragmentary end view of the grinding ap- United States Patent O GRINDER FOR INVOLUTE BACON KNIFE Raymond A. Raine, Oak Lawn, 11]., assignor to Armour and Company, Chicago, 11]., a corporation of Illinois Filed July 17, 1957, Ser. No. 672,415

5 Claims. Cl. 51-247) This invention relatesto an apparatus for the grinding of rotary knives. It is more particularly related to a portable apparatus for the. sharpening of involute bacon knives. i y V i In the conventional bacon'slicing machinery the rotary In at least one particular type of bacon machinery the rear portion of the guard is rigidly mounted whereas .the forward and top part of the guard is movably. mount- '"e d upon a hinge so as to permit the blade to be exposed.

In the maintenance .of the slicing machine theblade is ordinarily honed by hand at least once every two or three days by mechanics familiar with the machinery. As the .cuttingedge of the blade is worn down by thehoning it is necessary to removethe blade from the machine aiid togrind down the knife edge so as to makepossible a sharp rather than a blunt cutting edge. The hon: ing of the knife edge is a'very delicate operation, and consequently many bladesare improperly honed and must be removed from the machine and ground again before they can be sharpened and used. The honing of the blade is a time consumingoperation and therefore a costly operation even aside from the additionalfcost incurred befreground.

-when blades are improperly honed and therefore must honing operation which previously has heen done by It. is a more particular object of the invention'to upon rotatable blades whose 'cutting edge is] of involute.

tional view of the guide block and grinder wheels in operating position on the knife edge.

Fig. 8 is an enlarged fragmentary view of the relation of the various surfaces of the knife edge and of the grinder wheels. V

As mentioned before, in many cases bacon slicing machinery is so designed that the upper'and forward portion of the knife guard may be removed, thus exposing the knife blade immediately forward of the rear guard. Inthe particular embodiment of the grinding apparatue of the present invention shown in the drawings, there is provided a means for attaching the grinding apparatus to this rear portion .of the knifeguard. Referring now partieularly to Fig. l the permanently mounted rear knife guard of the slicing machine is designated by the numeral 11. This guard 11 extends perpendicularly from the'table'top'18 of the slicing table and is particularly convenient" for the mounting of the present grinding machinery." In many such slicing machines the guard 11 extends somewhat higherthan the knife while in other machines (as in Fig. l) the guard 11 may not extend to p the height of the knife.

" "Thegrinder of this invention is mounted upon the rear guard .11 by means of a guide rail mount 20 i which is affixed to the rear guard 11 by means. of a pressure elamp '21 as shown in Fig. 1. Attached; to the guide rail mount 20 is the guide rail 22 The guide rail 2 2fits immediately inside the rear guard 11 while the guide rail mount 20 extends over and around the outside .of the rearguard 11. The grinder support 30 is and adapted to move Within the grooves 24. Thus it isseen that the grinding machinery framework can easily moye vertically without sideways motion. The guide wheels are fixed to the grinder support 30 by means of their ownaxles 27. i

A horizontal supporttbar 31 is rigidly mounted upon the vertical grinder supports 30. Mounted immediately beneath the horizontal support bar 31 is the block shape. Further objects and advantages of the invention will be seen as the specifieation proceeds.

I In the accompanying drawings; H h 1 Fig. 1 is avertical cross-sectional view of an apparatus [embodying the novel features of the knife grinder. of

. the present invention. 1

Fig. 2 is a fragmentary yertical cross-sectional view showing amounting of the' guide block and guide supthegrinding wheels and guide block in operating position. Fig.36 is "A fragnientziry end view of theguide an and 45 which supports and maintains the alinement of the grinder wheels. An electric motor 70 or other source of power can conveniently be mounted on horizontal of the belt 55. and pulley 54.

' The rotary knife blade 13 as is shown .in Fig. 5 is of involute shape. It is also concave having a slight bend at point 17 onits surface. The cutting edge itself is formed by "the vertical surface 16-and by surface .14,

each of which is subject tothe action of the grinding wheels of the present apparatus. T he knife is also beveled near its cutting edge to provide a second surface 15 whichmakes a less acute angle with vertical surface controlled by a guide'block and support assembly which is shown in cross-section'in Fig. 2 and in an end viewin -.Fig. 3. Greater detail of the guide block and support are shown in Fig. 7. Referring now to Fig. 7 it will'be seen that ;the guide block 36 is mounted upon a guide block frame 38 by means of'screws 39. The guide block (frame; 38 is mounted by means of bolts 37 to a guide support 3 2. On referring to Fig. 3 it will beiseen that it the gnide supp'ort 32extends initsnarrower portiunitii t qg h' th h rizq ta Fl I PRO j n 31;-andl. affixed thereto by means of the nut 34 and upper nut 35.

.{ th guide block bfi'tFigi 15 and 16 Without contact with the surface 14. The rotary blade as seen inFigLS rotates in a counterclockwise -'direction. The'relationship of the guide assembly; knife [and grindingwheels is'seen best in Fig. theguide assembly is on ,thejsid'e of the grindingwheels immediately preceding the grindingwheels as the knife tu'rnsin.

its operative direction. Q The grinding apparatus therefore can be designed for knives rotatingin eitherdi'rection.

Also attached to the horizontal guide support 31 is the block 45 in whichthe shafts of the grinding wheels are mounted. The drive shaft 48 of the burr grinding wheel 50 is positioned in a;horizontal shaft aperture and is maintained in positionby means of bearings 49 which are attached to the shaft 48. The collar designated in Fig. 1 as 49;: rotates and is a part of the bearing 49 which is movably fixed to the shaft 48 byv means of set screw 56. At the end of the shaft 48 nearest the knife l 13 there is mounted a burr grinding wheel 50. The burr a grinding wheel 50 is attached to the drive shaft 48 by any convenient means such as by means of thenut 51.

I The grinding wheel 50 is so alined as to present its grinding surface 52 in alinement with the 'vertical surface 16 of the knife 13. If desired the drive shafts 48 and 60 may be spring loaded to provide even pressure of the grinding wheel surfaces 52 and 62a on the surbe obtained by providing a spring under tension between the block 45 and the bearings of the'drive shafts.

In a second shaft aperture in block 45 there is mounted a drive shaft 60. In Fig. 1 this drive shaft isshown passing in front of and at an angle to the drive 'shaft 48. Drive shaft 60 is provided with bearings 61 which asin the case of bearings 49 are movably fixed to the shaft by means of set screws 61a. At the end of the shaft closest to the knife there is mounted a grinding wheel 62. This grinding wheel 62 is formed so as to bear upon the surface 14 of the knife only in the limited area comprising the surface 14.

l ower may be supplied to drive the drive shaft 48 by any convenient means such as in the present preferred 4 embodiment by an electric motor 70 mounted at the top of the apparatus upon horizontal support bar 31'. Power istransmitted from this electric motor to the pulley of the drive shaft 48 by means of a belt 55. The pulley 54 is aflixed to drive shaft48 by means of a collar '53 k and set screw. As shown in the center of Fig. 1 and also in Fig. 4 drive shaft 48 is provided with a gear 57 which is a part of and attached to its collar 58 and is affixed to drive shaft 48 by means of set screw 59. Corresponding to this gear is the worm gear 64- of the drive shaft 60. The collar 65 forms a part of worm gear .64 and is afiixedto shaft 60 by means of a set screw 66. 'Therefore' when drive shaft 48 rotates it supplies rotary v power to the drive shaft 60 by means of slidably fitted worm gear arrangement.

The position of the block 45 underneath horizontal support bar '31 may be adjusted by means of the adjustment screw 67 which 'is mounted in a portion 31a of the support bar 31. Upon turning the adjustment screw 67 the block 45 is caused to slide along beneath its support 7) is notched to fit over sur- -faces 15 and 16 and to ride above and upon surfaces identical involute shape having its block is then resting upon the knife edge or on a cam surface afiixed to the knife having a guide surface equidistant from the'knife edge." Power is then apphed to the grinding wheels and the knife is moved slowly about its axis so as tocontact'the grinding wheels with the portion of the knife to be sharpened. As-the involute blade is rotated forward and back the block slides along the knife surface .on the cam surface thus raising and lowering the entire'grinder framework assembly and the attached grinding wheels to maintain a proper relationship of knife edge and grinding wheels. While in the foregoingspecification specific embodiments of the invention have been set forth for the purfaces 16 and 14 ofthe knife; Such spring loa'ding'may pose of illustration, it will be apparent to the skilled in the art that this invention is susceptible of many other embodiments and that many of the specific details hereln may be varied-widely without departing from the basic concept and scope of the invention.

I claixnz d V I i I 1. In a sharpening apparatus for rotary involute slicing machine knives, the combination of a grinder framework, means for movably mounting said grinder framework 1n automatically adjustable relationship to said slicing machine knife,-a guide mounted on said grinder framework, said guide being adapted to ride upon the knife edge and thereby to automatically maintain a fixed relationship 7 between the grinder framework and .the knife edge, a

rotary grinding wheelmounted on said grinder framework and adapted, to be rotatedat a point in fixed relationship to, said grinder framework and thereby to said guide and to the rotary knife upon which said guide is carried.

2. In an apparatus for grinding and sharpening rotary V knives of involute shape, the combination of a grinder framework, means for grinding knives, said means being adjustably mounted on said grinder framework, means for movably mounting said grinder framework in automatically adjustable relationship to said rotary knife, a

guide mounted on said grinder framework, said guide being adapted to ride upon and slide along the upper portion of the blade of said involute rotary knife at a point which is fixed in relation, to horizontal motion and the aXis of said rotary knife and thereby to automatically maintain a uniform distance between the cutting edge of said rotaryv knife and said grinder framework.

3. In a sharpening apparatus for rotary involuterslicing machine knives, the combination of, a substantially vertical slide rail mounted in fixed relationship to said slicing machine and supporting a grinder framework in proximateirelationship' to the knife of said .slicing'ma- Qbar 31. To facilitate this-motion the block'mounting" screws46 are passed through an elongated hole in-the .support bar 31. Thus by loosening support screw 46 and sliding the block along beneath the bar, it may'be'so adjusted as to'present the grinding Wheels in' the pr'oper relationship to the rotary knife 13. 1 Variations of the particular structure may be made without departing from the operative principle's of the invention. We'have found it desirable in some-embodium'entsof the machine to provide a 'cam'attached to'the. i face of therotary knife about the =axle 12 ibf 'thefknife. I F-{he cam cenf be of-lesserdiameter thaii the'knife b'utbf chine, a. grinder framework movably mounted upon said slide rail, means for grinding slicing machine knife blades, a member adapted to maintain a uniform distance betweenthe cutting edge 'of said rotary knife and. said grinder framework and thereby maintaining uniform'felationship between-said grinding means and said rotary knife said member being substantially rigid and. extending between said grinder framework and said rotary knife. 4. An apparatus for grindinga rotary knifejcomprising a grinder carriagemeans for mounting said grinder carriagein proximate relationship to saidrotary knife, said means for mounting said grinder carriage being adaptedto provide for vertical motion of said grinder carriage ,during the grinding operation, a rotary grinding wheel;

arotatable shaft 'suppb'rtin'g 'said grinding wheel, means f adj rss n at? sardi e e s shaft upon said grinder carriage, said means for mounting said grinding wheel and said shaft being substantially in the form of a block adjustably aflixed to said grinder carriage and having apertures adapted to receive said shaft, positioning means for maintaining said grinding wheel in proper positional relationship to said rotary knife by supporting said grinder carriage upon said rotary knife at a point on said rotary knife in constant relationship to the point on the cutting edge of said rotary knife which is in contact with said grinding wheel.

5. An apparatus for grinding and sharpening involute rotary knives, comprising a grinder carriage, means for movably mounting said grinder carriage in proximate relationship to said involute rotary knives, means for grinding said involute rotary knives, said means being adjustably mounted on said grinder carriage, and a substantially rigid positioning means mounted to said carriage and in contact with a cam surface, all points of said cam surface being substantially equidistant from corresponding points on the cutting edge of said involute rotary knives, Whereby said means for grinding knives are automatically maintained in proper relationship to the cutting edge of said involute rotary knives.

UNITED STATES PATENTS References Cited in the file of this patent 753,630 Rich Mar. 1, 1904 772,305 Williams Oct. 11, 1904 1,083,687 Larson Jan. 6, 1914 1,731,533 Hufl Oct. 15, 1929 2,338,995 Burns Jan. 11, 1944 2,738,628 Lust Mar. 10, 1956 

